The term curtain wall refers to a type of building construction in which an exterior non-load-bearing wall is supported in front of the structural frame like a curtain. U.S. Pat. No. 5,937,600 describes a casing bead or starter track for the installation of stucco-covered, curtain wall type, foamed siding applied to the exterior of buildings prior to the application of an over-applied coating of a stucco finish or the like. The device described in this patent comprises a generally U-shaped channel and incorporates in its front wall apertures for the infiltration of caulk, stucco or the like during erection and in its rear wall striations that serve to grip an inserted foam panel and any included caulking or the like.
While the casing bead as just described offers enhanced resistance to moisture infiltration as well as security of installation, there remains a continuing desire to improve the adhesion of the over-applied stucco finish to the casing or starter bead as described in this U.S. Patent. Thus, while infiltration of the over-applied stucco into the apertures in the front wall of the prior art casing bead channel provides some adhesion of the over-applied stucco finish, it would be highly desirable if some means could be provided to further improve the adhesion of the over-applied stucco finish to the casing or starter bead to improve the overall quality and durability of the installation.